Uniform Cylinder
// h=height, r1=bottomRadius, r2=topRadiuscylinder(h, r1, r2, center = true/false);// All are equivalent; use one.cylinder(h=20, r=10, center=true);cylinder( 20, 10, 10,true);cylinder( 20, d=20, center=true);cylinder( 20,r1=10, d2=20, center=true);cylinder( 20,r1=10, d2=2*10, center=true);
